What is the difference in hydrogen ion concentration comparing solutions with a pH of 2 and pH of 4?

1 Answer
Sep 7, 2016

A hundred fold difference in #H_3O^+# concentration applies

Explanation:

#pH=-log_10[H_3O^+]#. And thus each #pH# unit represents a tenfold difference in #[H_3O^+]#, i.e. hydrogen ion concentration.

Thus if #pH=2#, #[H_3O^+]=10^(-2)*mol*L^-1# #=# #0.01*mol*L^-1#

And if #pH=4#, #[H_3O^+]=10^(-4)*mol*L^-1# #=# #0.0001*mol*L^-1#.

Thus when #pH=2#, #[H_3O^+]# is #100xx# more concentrated than when #pH=4#.